Biomimetic cell culture substrates

Abstract

Embodiments of the presently disclosed subject matter provide biomimetic cell culture substrates comprising highly tunable patterned polymer nanofiber matrices capable of modulating expression of critical self-renewal factors and markers of cell-cell interaction to maintain stemness of human mesenchymal stem cells in vitro. Embodiments of the presently-disclosed subject matter also provide scalable, highly repeatable methods of making biomimetic cell culture substrates by hot pressing thermoplastic polymer films into femtosecond laser-ablated nanopore molds to form patterned polymer nanofiber matrices on flat thermoplastic substrates.

What is claimed is: 
     
       1. A method of manufacturing a cell culture substrate, consisting of:
 providing a mold having a patterned array of nanopores laser ablated in a surface thereof; 
 pressing a thermoplastic polymer film against the surface of the mold; 
 heating the polymer film to a temperature greater than the melting temperature of the polymer; 
 allowing the polymer to melt and infiltrate the nanopores in the absence of a solvent; 
 cooling the melted polymer to a temperature below the melting temperature of the polymer until the melted polymer solidifies; and 
 removing the solidified polymer from the mold as a cell culture substrate; 
 wherein the cell culture substrate comprises a plurality of freestanding polymer nanofibers integrally formed on a surface of the film along an X-axis and a Y-axis at the same or different intervals along either axis, the nanofibers having a length of at least 10 microns, a base portion that extends at least 1 micron outwardly from the surface of the film at an angle substantially perpendicular to the surface of the film, a tip opposite the base portion, and an average diameter between the base portion and the tip of from about 0.10 microns to about 1.20 microns.